The present invention generally relates an operation management technique of an SSP (Storage Service Provider) which owns a storage network, namely a SAN (Storage Area Network) and a plurality of NASs (Network Attached Storages), and provides a storage region (storage resource) to a client, while the storage network is constituted by coupling a plurality of storages with a plurality of servers in a high speed. More specifically, the present invention relates to a storage resource selection technique, a disaster recovery technique, and a cost reduction technique, which are met with requirements of clients under optimum condition.
Conventionally, storage devices have been used as appendix articles, namely external storage units of servers such as disk devices and tape apparatus. However, in connection with importance of information as well as extensions of storage capacities, data exchanges and data sharing are required among a plurality of systems. As a result, NASs (Network Attached Storages) having large capacity storages, a common carrier leased network which couples a storage group to a server group in a high speed, and SANs (Storage Area Networks) have been popularized. In such an SAN, storage consolidation is realized by employing a server group and a storage group, so that higher efficiencies of system operation may be realized.
Generally, a storage administrator within an enterprise uses a management tool in order to manage topology of an SAN, and also to operate/manage connections between NAS appliances and a server.
In accordance with a management tool, various information such as capacities, empty capacities, and network topology related to storages and servers are acquired, and then servers, storages, and network appliances, which are connected to an SAN are displayed on a display screen. Since icons related to the respective appliances are clicked on the screen, more detailed information (for example, capacities of respective storages and states of storage assignment to servers) can be displayed on the display screen. Then, not only the management information is acquired/displayed, but also storages and logical areas within storages are allocated to the server, and these allocations are deleted, or changed. Also, since back-up setting operation/back-up tool are combined with the above-described management tool, utilization of a system may be effectively increased.
However, storage operation administrators employed in enterprises are facing to various problems, for instance, increases of cost with respect to increases of storages which are not predictable in recent years, complex structures of management tools in various fields, space saving aspects of installation spaces for storages. These problems may be solved in such a manner that while information resources owned within enterprises are transferred in an outsourcing manner to such an enterprise which exclusively operates/manages storages, all of storage operations/managements are consigned to an external enterprise. As such an enterprise which operates/manages storages and lends storage resources to clients, an SSP (Storage Service Provider) is known (see “Data Storage Report 2000” of Japanese monthly magazine “Computopia”, on pages 36 to 37).
FIG. 13 is a network structural diagram for indicating operation modes of an SSP (Storage Service Provider) 103.
A client who wants to consign information resources provided within the own enterprise (firm) in an outsourcing manner installs a customer's server 108 corresponding to the server of the own firm within the SSP 103, and accesses from a customer's console 100 installed in the own firm to the customer's server 108 of the own firm. The SSP 103 is constituted by a storage device (106, 107), an SAN 105, and a customer's server group (108, 109, 110). All of nodes which are connected to the SAN 105 are managed by a management server 104. The SAN 105 is arranged by a fiber channel, the Ethernet, or the like. Both the customer's console 100 and the customer's server 108 corresponding to the server of the own firm are connected to each other by way of either an NFS (Network File System) or a CIFS (Common Internet File System), or by way of a common carrier leased line, while using a VPN (Virtual Private Network) 101 on the Internet 102. The customer's console 100 is connected via the Internet 102 to the management server 104.
In the SSP 103, in such a case that a storage area allocation request is issued from the client via the customer's console 100, the SSP 103 interrogates access performance, reliability, usage, and the like, which correspond to the request of the client with respect to the storage, from the customer's console 100, and then selects such a storage resource which is fitted to the request. When the storage resource is selected, the SSP 103 uses a management tool. The management tool continuously acquires from the storage, a value indicative of a state of a storage resource (will be referred to as “resource state information” hereinafter), while this resource state information corresponds to an operation state of a storage resource, a use condition thereof, and a throughput thereof. While the above-described resource state information is used as a selection factor, the SSP 103 selects such a storage resource fitted to the request of the client 100 from the resource state information.
Next, the SSP 103 assigns the selected storage resource to the customer's server 108. In order to assign a storage resource to the server 108, the previously existing SAN topology management tool, and a volume management tool contained in a storage may be used. Since the above-described storage resource is assigned, the customer's console 100 may use the storage resource which satisfies the performance request in the customer's server 108. Also, information saved in the customer's server 108 may be viewed, set, and changed from the customer's console 100.
FIG. 14 is a flow chart for describing a process operation of a storage resource assignment to the customer's server 108.
In this flow chart, the SSP 103 has continuously acquired resource state information 200 contained in the storage, such as an operation ratio, a load ratio, an empty storage, an RAID level, DISK performance, and the like as to the storage (step 201). Under this condition, in such a case that the SSP 103 receives both a rental request of a storage region, and a request 202 related to a capacity and performance with respect to a storage resource from the customer's console 100 (step 203), this SSP 103 selects such storage resource which is fitted to the request of the client, while using the previously-acquired resource state information 200 as a selection factor (step 204). Then, the SSP 103 assigns the selected storage to the customer's server 108 (step 205). To assign this selected storage resource, the presently-existing SAN topology management tool, or the assignment tool for the volume within the storage is used. The SSP 103 notifies such a fact that the storage resource is usable via the management server 104 to the customer's console 100 (step 206).
Also, the SSP 103 copies necessary data as back-up data with respect to the storage resource used by the customer's server 108 in order to recover the necessary data when a trouble happens to occur. In this case, in order that the back-up data is not deleted at the same time due to the occurrence of trouble, while another storage device different from the storage device used by the client is secured, the SSP 103 copies the data stored in the storage resource.
In the above-described prior art, the following mode is represented. That is, while the SSP 103 owns the servers 108, 109, 110 of the clients within the SSP 103, the SSP 103 causes the customer's servers to use the SAN 105. However, there is another mode. That is, in the SSP 103, a network is connected from the SAN 105 provided in the SSP 103 is directly connected to a customer's firm, so that the SSP 103 may provide a storage service. In this alternative case, the customer's server 108 shown in FIG. 1 may become a network structure which is located at the place of the customer's console indicated in FIG. 13.
As previously described, in the prior art, either the management tool or the storage administrator selects such a storage resource which is fitted to both the capacity and the performance requested by the client based upon the resource state information of the storage resource, and thus, may realize the assignment of the selected storage resource to the customer's server. Also, since the data stored in the storage resource are copied as the back-up data, the high utility of the SSP may be maintained.
In the conventional technique, while resource state information (operation condition, capacity, use condition, throughput and the like as to storage resource) within each of storages, which is obtained from the management tool, is used as a selection factor, such a storage resource is selected and allocated to a client, which can satisfy both a capacity and access performance of a storage requested by this client.
However, in such an SSP which may unitedly provide resources and NASs on an SAN, distributed in long distances, to a client by using a wide area network (WAN), a large number of composite networks are used in the SSP. In such a network, network access time between the storage resource and the customer's server may give an influence to access performance to a storage. As a result, only such resource state information (operation ratio, disk performance, and the like) corresponding to a factor for determining access performance within the storage resource can hardly satisfy entire access performance which is required by the client.
Furthermore, in the case that while storages which are broadened and distributed over long distances are effectively utilized, and also back-up operation capable of solving disaster problems such as an earthquake is carried out, positional information such as installation areas of storage units is not acquired in the presently available management tool. As a consequence, this presently available management tool owns no means capable of intentionally selecting storage units which are located far from a designated distance.
Also, in the case that a client which utilizes an SSP moves, since network access time required from a move destination to a storage resource is not considered, there are some possibilities that data is transferred to such a storage located near the move destination of the customer's server. Under such a circumstance, work cost required to transfer the above described data is necessarily required every time the client moves.